The MPC5777C FlexCAN supports detection and correction of errors in memory read accesses.

Most probably the issue Paolo has is due to this feature that is enabled by default. The ECC error may have occurred due to module not being initialized properly or if the debugger is reading/displaying non initialized registers.

The ECC feature can be disabled by setting bit ECCDIS in CAN_MECR. Note that bit ECRWRDIS in the same register prevents writes to the register unless it is cleared first. Disabling ECC does not impact the normal operation of the FlexCAN.

I placed FlexCAN demo code tested on the MPC5777C EVB in the community; see